SnowSlider - Blogging From the mountains by ise

I’d posted about my Garmin etrex VISTA Cx GPS recently and basically said I was quite happy with it. Since then I’ve noticed a fairly serious problem with it. To recap, I really use it in two ways, to navigate between way points I’ve entered ahead of time and to store my track for geo-tagging photographs. For these things it’s been working fine.

But, a couple of weeks ago we were descending Teysachaux, a local peak, and I happened to glance at the GPS and noticed it was displaying the wrong coordinates, the North position was correct but the East position was wrong placing me 20km further south. I presumed I’d programmed the wrong map datum onto it and didn’t think too much more about it. Later when I checked this at home I found exactly the same error with the same margin and confirmed that it was using the Swiss Grid CH1903. Some more tests showed that the latitude and longitude was perfectly correct and that positions transferred to the PC would be displayed correctly, I presume that the base system is latitude and longitude and that the translation is in error.

I think if I didn’t actually really just use a normal Swisstopo paper map I’d probably have noticed this sooner, in fact I’m not sure if this is new behaviour or it’s been doing this since new. Possibly one of the firmware updates introduced this. Anyway, I managed to contact Garmin by phone as their trouble ticket system wasn’t working and a couple of days later they’ve confirmed the problem and are suggesting they’ll be an update sometime in the next month to address this

Towards the end of the ski season I got the Garmin eTrex Vista Cx GPS unit which I’ve mentioned before and been using to produce some track files for viewing in Google Earth. The real reason I bought this was for navigation, I’d had an older GPS a few years back prior to the removal of selective availability when it really just didn’t work accurately enough. Yet again I was dubious, this time about GPS for navigation, my problem is that I believe nothing can be a substitute for being able to read a map and navigate in the mountains with map and compass regardless of the weather conditions. However, map and compass aren’t always quick to use and a couple of off-piste trips skiing alone when the visibility was appalling made me think a GPS might be useful particularly if I saved some common local waypoints onto it.

I opted for the Garmin eTrex Vista Cx as it was a mid-range mapping unit with a barometric altimeter and electronic compass included. Most GPS can tell you altitude but they’re not renowned for their accuracy so you really need a barometric altimeter if you want some accuracy. I’ve also got the SwissTopo maps for the device for the whole of Switzerland which are in the proprietary Garmin format for use with the MapSource product.

The software has been a nightmare, when I first tried to initialise the maps the Garmin server wasn’t working and I couldn’t unlock them. You need two different keys as well, one to get the maps installed onto your PC and another to unlock them to get them onto the device. Later when I moved computer the registration failed, as I’d already installed on my old desktop and laptop, so I had to call a premium rate line to get it re-enabled, this is common practice in the software industry now, for example Microsoft do it, but Microsoft are pretty slick so while the principle is irritating at least the practice isn’t. The Garmin principle and practice was irritating though.

Read on for the field test and tips for integration with Google Earth……….

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